Current collector



Feb. 14, 1939. w, SCHAAKE 2,147,460

CURRENT COLLECTOR Filed Sept. 13, 1935 Hy, /I

Patented Feb. 14, 1939 2,147,460

UNITED STATES PATEN T `OFFICE 2,147,460 CURRENT COLLECTOR William Schaake, Pittsburgh, Pa., assigner to Westinghouse Electric & Manufacturing Gompany, East Pittsburgh, Pa., a. corporation 4of Pennsylvania Application September 13, 1935, Serial No. 40,376 2 Claims. (Cl. lill-59.1)

My invention relates, generally, to current colprovide for collecting current from a trolley wire lecting equipment for electric vehicles. It has with a minimum of wear on the trolley wire particular relation to slider shoes for engaging and friction between it and the current collecting with and collecting current from trolley wires, device.

` 5 and it constitutes an improvement over the trolley An important object of my invention is to proshoes of the type shown and described in my vide for simultaneously lubricating a trolley wire 'Patent No. 1,841,552, which is assigned to the and collecting currents therefrom. assignee of this application, Another object of my invention is to provide In the trolley shoe sho-Wn in the aforesaid patfor casting a lubricating and current conducting ent, a main body member is provided that is medium in a slider shoe which is disposed to en- 10 arranged to be cast around an insert which is gage and collect current from a trolley wire.

Composed `of a metal diiferent from and which Another object of my invention is to provide may be harder than the trolley shoe itself. For a slider shoe for collecting current from a trolley example, in this patent, it is stated that a nitrided wire having a non-metallic insert cast integrally steel insert may be provided in order to prolong with the shoe to engage the trolley wire. 15 the life of the slider shoe. Still another object of my invention is to pro- When such a construction is used, I have found vide a slider shoe for collecting current from a that there is considerable wear on the trolley trolley wire having a graphitized carbon insert wire, and that while the life of the slider shoe integrally formed with the shoe to engage the is materially prolonged, the resulting wear on the trolley wire.

. 20 overhead system produces a factor which cannot Other objects of my invention will in part be be neglected. 'Ihere is a tendency for the trolley obvious and in part appear hereinafter.

wire to be-rapidly worn out due to its engage- My invention accordingly is disclosed in the ment with the hardened steel surface, and as a embodiment hereof shown in the accompanying result it must be replaced at relatively frequent drawing, and comprises the features of construc- 25 intervals. This rapid wear of the trolley wire tion, combination of elements and arrangement is due principally to the relatively great fricof parts which will be exemplified in the contional force which is exerted on the trolley wire struction hereinafter set forth, and the scope of and which results from lack of a lubricating the application of which will be indicated in the medium between the slider shoe and the trolley appended claims.

30 wire. Heretofore, it has not been possible to For a more complete understanding of the satisfactorily provide for lubricating a slider shoe nature and scope of my invention, reference may to reduce the frictional forces between it and be had to the following detailed description the trolley wire. Attempts have been made to taken in connection with the accompanying provide a lubricating medium which is movable drawing, in which: 35 relative to the slider shoe. Howe-ver, such equip- Figure l is a view, in side elevation, of a slider ment is expensive in initial cost and also in its shoe embodying the features of my invention; upkeep. Furthermore, it adds to the weight of Fig. 2 is a longitudinal cross-sectional view of the pole-head supporting the slider shoe and is the slider shoe shown in Fig. 1; also objectionable for this reason. Fig. 3 is a View, in end elevation, of the slider 40 There has been no practical solution in the past shoe shown in Fig. l; to the problem of collecting current from a trol- Fig. 4 is a sectional View taken along the line ley wire by means of a slider shoe, and at the IV-IV of Fig. 2; and same time providing for reducing the frictional Fig. 5 is a sectional view of a modied form forces therebetween by supplying a lubricant beof the invention. 45

tween the slider shoe and the trolley wire by the Referring now particularly to Fig. 1 of the engagement of the slider shoe itself with the drawing, the reference character l@ designates, trolley wire. generally, a slider shoe, the main body member It is, therefore, an object of my invention to of which may be of cast steel, cast bronze, cast provide a self-lubricated slider shoe for collectaluminum or aluminum alloy. Any of these ma- 50 ing current from a trolley wire which shall be terials may be employed, as well as other suitsimple and eflicient in operation and which may able materials, depending upon the service conbe readily and economically manufactured and ditions which are to be met by the slider shoe. installed. As illustrated in the drawing, the slider shoe The principal object of my invention is to I0 is provided with a centrally located groove Il, 55

the surface of which is arranged to engage a trolley wire (not shown). The groove II terminates in upwardly extending lips I2 which form the sides thereof. In order to mount the slider shoe I in a pole-head (not shown), depending ears I3 are integrally formed with the body member and are provided with openings I4 through which a suitable bolt or shaft may be positioned for securing it to the pole-head.

In order to reduce the resulting Wear on the trolley wire to a'minimum and also to provide for collecting current therefrom, I have provided for casting an insert I5 integrally with the body member of the slider shoe Ill, which may be nonmetallic in composition and which inherently provides` a certain amount of lubricating effect as the slider shoe IU is moved along the trolley wire. In particular, I have employed an insert I5 which is composed of carbon and also an insert which is composed of graphitized carbon. By the term graphitized carbon I mean a material composed principally of carbon but having thoroughly intermixed therewith graphite, which I have found constitutes a suitable composition toprovide the required amount oflubricating effect between the slider shoe I0 and the trolley wire. In the event that it is desired to increase the conductivity of the insert I5` beyond the degree which may be obtained when carbon or graphitized carbon is used, the insert I5 may also have uniformly mixed therethrough a small amount of copper. By this means it is possible to increase the conductivity of the insert I5'and at the same time retain its lubricating qualities due to the fact that it is composed of carbon or has provided therewith a certain amount of graphite.

Referring now particularly to Fig. 5 of the drawing, it will be observed that the shoe I2 has embedded along the groove II two inserts I6 and another insert I'I centrally located therebetween forming what may be termed as a composite insert. The inserts I6, for example, may be composed of carbon, graphitized carbon, or copper graphitized carbon, as set forth hereinbefore, while the insert I1 may be composed of nitrided steel or other hardened material, as set forth in my aforesaid patent. It will be understood that the insert I'I may be composed of carbon in its various combinations, and that the inserts I6 may be composed of hardened material.

When the composite insert is used, it is possible to combine the wearing qualities of the slider shoe described in my patent and at the same time to obtain the lubricating qualities which are desirable to reduce the Wear on the overhead. When the slider shoe I2 is composed of aluminum or aluminum composition, an extremely desirable combination is provided, since the shoe itself is light in Weight, has exceptionally long life because of the hardened insert or inserts, and is provided with lubricating qualities through the use of the carbon or carbon combination inserts.

In constructing the slider shoe of the types set forth herein, I preform the insert I5 or the inserts I6 and I1 and then position it or them in the mold in which the molten metal is poured of which the body member is formed. Due to the fact that the carbon insert I5 has a relatively high melting point, as Well as the inserts I6 and I'I, it is possible to readily cast them in the shoe so that a unitary construction will be provided.

When the slider shoe Ill is composed of aluminum, the weight thereof is materially reduced as compared with the weight when steel or other heavy metals are used. Furthermore, the Wear on the trolley wire is reduced when the shoe IIJ is composed of aluminum and an insert such as the carbon insert I5 is employed. This is due to the fact that the ends of the groove II are soft and do not dig into the trolley Wire as the shoe passes from underneath special overhead fittings such as frogs, cross-overs and the like onto the trolley wire. It will, therefore, be observed that it is advantageous to construct the shoe I0 of a light and soft metal such as aluminum and to provide in it an insert I5 either cast integrally therewith or secured in a suitable manner thereto and composed of the materials set forth hereinbefore or composed of a hardened insert such as is shown in my aforesaid patent.

I nave found that slider shoes of the type set forth herein may be readily constructed on a production basis in an economical and efficient manner. Due to the fact that the insert I5 is cast integrally with the body member of the shoe II), there is no likelihood that it will become broken or disengaged therefrom. I have found that it will remain in place and without breaking during the life of the shoe. I have also found that the insert I5 when composed of carbon, graphitized carbon or copper graphitized carbon has a remarkably long life, while at the same time the Wear on the trolley wire is reduced to a point where it is substantially negligible. It will, therefore, be understood that I have provided a slider shoe which is relatively cheap in construction, but extremely durable and having a long life, and which will cause substantially no wear on the trolley Wire with which it engages for the collection of current.

Since the construction herein may be altered Without departng from the scope of the invention, it is intended that all matter set forth in the foregoing description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. A slider shoe for collecting current from a trolley Wire comprising an aluminum composition body member provided with a longitudinal groove adapted to engage the trolley Wire, and a plurality of xed inserts formed integrally with the shoe disposed in the bottom of said groove for engaging said trolley Wire, certain of said inserts comprising a material having lubricating qualities and the remainder of said inserts comprising a hardened metallic composition.

2. A slider shoe for collecting current from a trolley wire comprising an aluminum composition body member provided with a longitudinal groove disposed to engage the trolley Wire, and a plurality of fixed inserts cast integrally With said body member along the bottom of said groove for engaging said trolley wire, certain of said inserts comprising a material having lubricating qualities and the remainder of said inserts comprising a hardened metallic composition.

WILLIAM SCHAAKE. 

